TALLAHASSEE — With the state pouring millions of dollars into research and marketing efforts, Florida’s citrus industry is approaching the end of the 2021-2022 growing season with its lowest production since around the start of World War II.

The U.S. Department of Agriculture released a report Friday that estimated Florida growers will fill 44.75 million boxes of oranges, grapefruit and specialty crops during the soon-to-end season, down more than 22 percent from the previous season.

Oranges make up the vast majority of the estimate, 40.7 million boxes, while grapefruit production is estimated at 3.3 million boxes and specialty crops are at 750,000 boxes.

Growers have pointed to a winter freeze hindering production this year. But in an initial forecast for the season, issued in October, the federal agency estimated growers would fill 51.7 million 90-pound boxes, which would have been the lowest output since the 1941-1942 season.

As it stands now, the estimated production is the lowest since the 1939-1940 season, when 43.995 million boxes were filled. That season, oranges accounted for 25.35 million boxes and grapefruit filled 15.9 million boxes.

Overall production during the 2020-2021 season totaled 57.94 million boxes, according to the federal report.

The industry has been on a downward trend for two decades because of issues such as residential and commercial development, foreign imports and an incurable bacterial disease known as citrus greening.

Senate President Wilton Simpson, a Trilby Republican running for agriculture commissioner this year, warned Thursday that another key issue is citrus growers leaving the industry because of the difficulty in making a living.

“In his view, as a citrus grower himself, finding and producing trees that are resistant to the devastating disease is paramount to the industry surviving in Florida as farmers are more willing to continue growing citrus if trees are more viable long-term investments,” Simpson spokeswoman Katie Betta said in an email.

A new state budget signed last week by Gov. Ron DeSantis provides $37 million for the industry. The biggest chunks of money are $17 million for Florida Department of Citrus marketing programs; $8 million for research programs; and $6.2 million for what is known as the Citrus Health Response Program.

In the federal agency’s forecast released Friday, projected orange production received a slight bump for the second straight month, going from an estimated 40.2 million boxes in May to 40.7 million boxes.

“While the gains may seem incremental, any increase is a positive,” Florida Citrus Mutual CEO Matt Joyner said in a prepared statement. “With support from leadership, research and a little more time, I’m confident we’ll come back stronger than ever.”

But orange production was forecast at 47 million boxes when the current season began and totaled nearly 53 million boxes in the 2020-2021 growing season.

The orange total for this season is the lowest since the 1942-1943 season, when 36.5 million boxes were filled.

Through the 1990s, the industry produced more than 200 million boxes of oranges a year, with overall citrus production topping 250 million boxes.

In Friday’s forecast, grapefruit production was pegged at 3.3 million boxes, down from 3.4 million in a May forecast and off 19.5 percent from the 4.1 million boxes filled in the 2020-2021 season.

The forecast for specialty crops, primarily tangerines and tangelos, slipped from 800,000 boxes in May to 750,000 boxes in June. The industry filled 890,000 boxes during the 2020-2021 season and began the current season with a 900,000 projection.